This invention relates to a picture changer for large-scale picture projectors, which latter term is to be understood to refer to a projector, in the upper surface of which a transparent plate is provided, through which light is transmitted from a light source in the projector. A large-scale picture of slide type or a transparent film with figures or text applied thereon is applied for use directly on said plate, and the picture is projected on a wall or the like. Colloquially, projectors of this kind mostly are called over-head projectors.
The normal picture changing procedure at these projectors is that a person manually changes the pictures where every picture is a film of about the same size as the plate. There exist also projectors, at which a long film is wound on a first reel at one end of the plate and can be rolled up on a second reel at the opposite end of the plate. Film can thus be advanced across the plate. Also this feed, however, is carried out manually.
The present invention relates to a picture changer of the aforesaid kind for large-scale picture projectors where every picture is a discrete picture and, thus, is not stored in a successive order on a long film.